In recent year, many light emitting elements used for display devices and the like have a structure in which a layer that includes a light emitting substance is sandwiched between a pair of electrodes. Such a light emitting element emits light when an excited electron, which is formed by a recombination of an electron injected from one electrode and a hole injected from the other electrode, returns to a ground state.
Many of these light emitting elements have a problem in that the driving voltage is increased with the accumulation of light emitting time.
In order to solve this problem, for example, the patent document 1 discloses an organic EL element using a compound with a certain structure, wherein the increase in driving voltage, and the like are suppressed in driving the organic EL element. [Patent Document 1]: International Patent Publication No. WO98/30071